Browse over 10,000 Electronics Projects using the Page Numbering provided at the bottom of each Page.

Ultrasonic Range Meter

Ultrasonic Range Meter

Measure the distance to an object within 25 cm to 8 meters using standard 40 kHz transducers. Takes around 20 samples per second.
Very useful for robotics! The first v2 version takes only 5 mA at 9v. The schematics are based on a project from Elektor dating from 1982!!!

Here again, the NOKIA LCD has been chosen for display. The circuit is controlled by a PIC16F877 running at 4 MHz.

At 20ºC/68ºF, sound travels through the air at 343,8 m/s. This is approximately 29µs for 1 cm. We want to measure the distance to an object. To do so, we will have to measure the time between the transmission & the reflected reception of an ultrasonic pulse.

Because the reflected pulse will travel twice until received back, we divide the speed by two. So, this makes 58µS for 1 cm.

This v2 version counts the amount of periods of 58µS it takes until the ultrasonic pulse is received back.

Visit Here for more.